Steam-engine.



1., M. KERN. STEAM ENGINE. APPLICATION FILED OCT- 24, 19,18

Patented Apr. 22, 1919.

PATET STEAM-ENGINE.

Specification of Letters Patent.

Patented Apr. 22, T9159.

Application filed October 24, 1918. Serial No. 259,464.

To all whom it may concern Be it known that I, Josnrn M. KERN, a citizen of the United States of America, and resident of Oswego, in the county of Oswego, in the State of New York, have invented new and useful Improvements in Steam-Engines, of which the following, taken in connection with the accompanying drawings, is a full, clear, and exact description.

This invention relates to certain llIIPIOVQ- ments in steam engines and refers more particularly to the construction of the piston as used in large, high powered locomotives in which the great Weight of the piston and high pressure of the steam contribute to produce excessive wear and frequent breakage of the packing-rings commonly employed in pistons of this type resulting not only in a considerable waste of power and fuel and loss ofschedule running time but also necessitates the Withdrawal of the. impaired engine from use for greater or less periods in order to make the necessary repairs and requires a number of engines to be held in reserve for, use in such emergencies, all of which adds materially to the operating expenses.

The main objects therefore of my present invention is to provide simple and eflicient means for obviating, to a great extent, these difiiculties and for materially increasing the life andworking eificiency of the pistons of this'type, first, by substantially balancing the pistons more nearly co-axial with the bore of the cylinder; second, by automatically equalizing the steam pressure at the inside and outside of the packing-ring immediately upon the exposure of either end thereof to the steam inlet-ports and, third, by using a single relatively long packingring extending the major portion of the length of the piston so as to better resist the angular strains to which it is subjected by the sudden application of high steam pres sure to either end thereof as it is exposed to the corresponding intake-port.

Other objects and uses relating to specific parts of the piston will be brought out inthe ollowing description.

In the drawings:

Figure -1- is a longitudinal vertical sectional View of a portion of a locomotive cylinder and piston movable therein, the piston being shown by full lines at the limit of its stroke in one direction and. by dotted lines at the limit of its stroke in the opposite direction.

Fig. 2 is a transverse vertical sectional view through the piston and adj acent portions of the cylinder showing a part of one of the intakeports.

Fig. 3 is a perspective view of the split packing ring forming a part of the piston.

In order that my invention may be clearly understood, I have shown a cylinder -1 as provided with the usual end heads 2 and -3- and steam-inlet ports 4, the latter being controlled by a valve 5 partly shown in Fig. 1-.

The piston -6- is reciprocally movable in the bore of the cylinder land comprises a head or collar 7 and a split ring 8 spring-pressed against the inner walls of the cylinder by coiled sprin s -9.

The piston-head or collar is firmly secured to the tapered end of a piston-rod 10 and is provided with an annular channel or grooove 11 in its periphery and extending the major portion of the length thereof to relatively short distances from the ends of the head or collar for receiving the riffg 8 of corresponding length, said head being also provided with a series of, in this instance, four radial pockets 12 in equally spaced relation circun'iferentially and extending inwardly from the annular recess or channel 11- for receiving the coiled springs 9.

The steam-inlet ports -4 open into op posite ends of the bore of the cylinder at the upper side thereof, the stroke of the piston being suchas to cause the ends of the ring 8 to alternately register with the corre* sponding ports as the piston reaches the limits of its strokes in reverse directions, that is, relatively small portions of the ends of the ring are caused to bemoved beyond the inner walls of their respective ports 4 to assure uniform Wear of that portion of the bore of the cylinder between said ports.

The upper 1 portions of the ring 8 which project beyond the inner walls of the ports 4 when the piston is at the limit of its stroke in either direction are provided with radial passages 13 therethrough to permit the entrance of the high pressure steam to the inner side of the ring when either end of the ring is registered with the corresponding port thereby equalas i izing or balancing the steam pressure int-ernally and externally of the ring.

The distance between the ports 'lis substantially equal to the length of the stroke of the piston plus the distance between the passages 13- in the ring 8 so that when the piston reaches the limit of its movementin one direction the correspond ing passage 13" will be registered with the adjacent port 'l and when it reaches the limit of its movement in its opposite direction the other passage 13- will be registered with its corresponding port thereby preventing excessive inward radial strains upon the ring by the sudden impact of the high pressure steam from the ports against the adjacent portions of the periphery of the ends of said ring when the piston reaches the limit of its movement in either direction at which time the high pressure steam is suddenly admitted to the corresponding end of the piston by the shifting of the valve 5-.

By extending the ring t-. the greater portion of the length of the piston affords a relatively long bearing thereof against the walls of the cylinder and enables it to better resist the tendency to angular or transverse tilting movement due to the sudden impact of the high pressure steam against the periphery of the ends thereof as said ends are alternately registered at their respective ports, and also serves-to guide the piston more evenly in its axial movement thereby effecting a more uniform wear of the ring and bore of the cylinder from end to end without liability of excessive friction or cutting of either of those parts.

It will be observed upon reference to Fig. 2- that the radial passages 13 are formed only in the upper side of the ring or in that side which is adjacent the steam inlet ports 4- and that the radial coiled springs 9- exert equal pressure upon opposite halves of the ring to hold them in contact with the walls of the bore of the cylinder -l, thus leaving a sufficient space between the inner face of. the ring and base of the annular groove 11 for the en trance and distribution of the steam entirely around the inner face of the ring for balancing purposes previously referred to.

As shown more clearly in Fig. 3-, the ring -8- is divided diagonally at -14- through diametrically opposite sides thereof and, if desired, the inner faces of the adja cent ends of the ring sections at one side may be provided with registering grooves -l5 intersecting the adjacent diagonal line of division for receiving a key l6 by which those ends may be held against separation when the ring-sections are assembled in the groove ll of the piston, key 16- also serving to enter a groove -l7- in the adjacent portion of the base.

of the annular groove 11 to assure the proper positioning of the passages 1.3 relatively to the ports 4.

The springs 9 in addition to their function ofpressing the ring-sections against the walls of the cylinder also serve to keep the main body-7 of the piston centrally within the bore of the cylinder or co-axial with the axis of the striding-box, as l8 in which the piston-rod l0 is guided, the two lower springs, Fig. 2-, serving. to rounteract the weight of the main body 7 of the piston thereby reducingthe-liability of sagging. of the end of the pistonrod to which it is secured and to that extent assisting in keeping said rod and main body of the piston coaxial with the bearing in the stuffing-box 18 through which the rod slides which assures a steady action of the iston and reduces wear. of the rod and stalling-box to a minimum and adds materially to the life ofthe piston.

The springs 9 are preferably located midway between the ends of the ring -8 and between the opposite sets of passages -l3 s0 as to cause all portions of therings to be pressed against the walls of the cylinder with equal force without in any way interfering with free passage of steam through the ports *-13- when the latter are alined with their respective ports l.

The operation of my invention will now be readily understood upon reference to the foregoing description and the accompanying drawing and while it is particularly useful in connection with the pistons of large locomotive cylinders of high power,-it is evident that it may be used'on the pistons of steam pumps and other apparatus.

hat I claim is:

1. In a steam engine, the combinationof a horizontally extending. cylinderhavingf the usual steam inlet ports, apiston reciprocally movable in the cylinder and provided with an annular recess extending the greater portion of its length, a split packingring; fitting said recess and" spring-pressedagainst the walls of the cylindensaid ring having radial openings therethrough near theends thereof to alternately register Withthe steam-inlet ports for equalizing the steam pressure on the-"inner and outer sides of the ring as they are registered with their respective ports. I

2. The combination of a steam cylinder having inlet-ports in opposite endscf one and the same side a piston reciprocally-movablein the cylinderand provided Wit-h an annular recess, a split-packing ring engaging the end Walls of the recess and provided with radial openings therethrough in spacedrelation axially'to alternately registerwith the corresponding inlet-ports as the piston reachesthe limits of its strokes in reversedirectionsa 3. In a steam engine, the combination of a substantially horizontal cylinder having radial ports in the ends of the upper side thereof, a piston reciprocally movable in the cylinder and comprising a main body having an annular recess and a packing-ring fitted in the recess, the upper side of said ring being provided near its ends with radial passages adapted to alternately registei with said ports as the piston reaches the limits of its movements in reverse direc tions.

4. In a steam engine, the combination of a substantially horizontal cylinder having radial ports in the ends of the upper side thereof, a piston reciprocally movable in the cylinder and comprising a main body having an annular recess and a packing-ring fitted in the recess, the upper side of said ring being provided near its ends with radial passages adapted to alternately register with said ports as the piston reaches the limits of its movements in reverse directions, and springs interposed between the ring and main body of the piston for holding said ring in contact with the walls of the cylin der and for supporting the main body coaxial with the bore of said cylinder.

5. In a steam engine the combination of a cylinder having inlet-ports in the opposite ends of one side, a piston reciprocally movable in the cylinder and comprising a main body having an annular recess extending the greater portion of its length and a packingring fitted in said recess, said ring being provided near its ends with radial passages adapted to alternately register with said ports as the piston reaches the limits of its movements in reverse directions.

6. In a steam engine, the combination of a cylinder having inlet-ports in the opposite ends of one side, a piston reciprocally movable in the cylinder and comprising a main body having an annular recess extending the greater portion of its length and a packing ring fitted in said recess, said ring being provided near its ends with radial passages adapted to alternately register with said ports as the piston reaches the limits of its movements in reverse directions, the main bddy of the piston being provided with radial pockets in equally spaced relation circumferentially, and coiled springs seated in said pockets and having their outer ends engaged with the inner faces of the ring for holding said ring in engagement with the walls of the cylinder and also for keeping the main body of the piston co-axial with the bore of the cylinder.

In witness whereof I have hereunto set my hand this 11th day of October, 1918.

JOSEPH M. KERN.

Witnesses:

JOSEPH T. MCCAFFREY, LOUISE FIRERON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

